I followed garyw 's well explained set and learn procedure several times but max revs end up at 1600 . I then tried adjusting from the top down ,with machine at full throttle in P set stepper motor arm at 2100 but my low idle is 1500 . I droped the cable down 1 hole on stepper motor arm (was in 2 from bottom) ,re learned and reset . I ended up the same more or less .I set it from the top down again so I have from 1400 to 2100 so it will just turn off with key . Not so bad , but it could be better . Machine was warm from the start . I have no manual or Dr Zeuss . The push pull cable and boll joints are A1 . It started late last year only revving to 1500 so an site I adjusted the push pull cable to get it to a reasonable working speed . After a weeks work one morning it failed to start so when I got there when I turned they key the stepper motor would just go ape until I turned the key off . I removed the stepper, replacing it with a vice grips. Arter the job finished ,I removed the 2 ECU's ,opened ,dried and sprayed with WD 40 . I refitted everything . That brings me back to the start of the post.
It's a difficult one mate without MPDr software. You would need to make sure the position sensor in the stepper motor reads 2.5v at idle. Basically the middle wire of the 3 pin plug on the stepper motor. After learnings complete, this should be far away from 2.50v give or take around 0.05v. Once at full rpm this should then be around 3.20v or thereabouts. MPDr will show a target speed and an actual speed. This will determine if the controller is deliberately holding the revs low or if it thinks its making the proper revs( it will indicate if the controller is at fault) I had a similar issue recently with a ZX70 and i had to put a controller(ECU) on it. Also, it would let me drop the revs but not raise them. Turned out to be a bad connection inside the controller. I wouldn't like to say that's your issue though without checking it due to the cost involved. Sorry i can be more help.
Thanks anyway garyw . When I get a chance I will put a multimeter on it .
Volvomad, did you ever solve this low speed throttle problem? I am experiencing the exact same issue with a ZX160LC and any help would be greatly appreciated.
Never got it right . There is a procedure on a thread here somewhere explaining how to reset the potentiometer in the stepper motor. That helped a good bit.
Thanks for the reply. I have tried the re-learning mode approach, which does seem to realign the low idle position, but when going to high idle it stops short at 1500-1700. I can adjust the clamp on the stepper motor shaft to increase the max speed to spec, 2150, but it seems after the next start or two the stepper motor has spun some, become weak, or something like that, causing the max speed to be lower than spec. I'll keep at it, thinking about throwing a new stepper motor on it.
So on zaxis 220 have seen the sensor at swing motor cause all kinds off throttle problems. Check for broken bare wires there. All so speed sensor by hyd pumps/flywheel. Wires become brittle (hyd heat) ground out
Another thing when doing relearn on throttle make sure a/c is off. Don’t know why but will cause problems on relearn
Thanks for the ideas. I have added a thorough look at the sensor wires to the list. Will also remeasure the voltages on the wires to see how they change and report back. I did perform the relearn with AC off, but will try again. When they say to leave throttle at idle when performing the learning procedure, does that mean with the dial turned to "L" or all the way counter clockwise, bottomed out? Should the idle 900rpm be at the "L" or with dial bottomed out?
Relearn should be done with throttle all the way down key off relearn switch on key on don’t start engine wait 5 seconds key off wait 5 seconds switch relearn switch off. Key on start see where low/high idle is
Alright, I went out and took a few measurements and tried the relearn again several times. Yesterday I ran the relearn routine and then adjusted "H" in power mode to be at 2050rpm or around there. I started it today and this is what I found: RPM at idle, lowest position, was 1186rpm (2.52V) RPM at L, was at 1527rpm. RPM at H, highest position, was at 1985rpm.(2.92V) I proceeded to go through the relearn procedure, turned off, wait 5s, switch to E, wait 5s, turn key to on(not started), wait 5s, turned key off, wait 5s, turned switch to mid position, wait 5s, started up machine After the learning procedure the rpms read this (basically a 300rpm drop across): RPM at idle, lowest position, was 875rpm. RPM at H, highest position, was at 1675rpm. (2.85V) I attached pictures of voltages read on the two connectors at the stepper motor.
Don’t really know what voltages you should see there. Did you check connection at swing motor sensor? Maybe mark shaft where you said thought was slipping try and verify if slipping don’t think is your stepper motor. My guess would be speed sensor or wiring
Thanks for the suggestions you have provided. I did check the wiring all around the pump and pilot systems. I checked the wiring, really only one connector, at the swing motor. All wiring looked fine, I wiggled them all pretty good and they did not seem brittle. Yesterday I took a sharpie and marked the stepper motor shaft at the clamp, through all of this the clamp does not appear to have moved on the shaft. It just appears the stepper motor is relaxing or failing to maintain position. There is also a hint that it does not have the total RPM range that it should, which I believe should be 950-2150. In different scenarios or times I get 950-1650 or 950-1650, or 1150-2150.
If you are in the service mode of the monitor what do you have listed on the right side of the display when a zero is on the left of the of the display? When you have your rpm issue what does item 14 read at that time compared to actual rpm? Items 2-5 and 17-22 all read zeroes when the levers are in neutral? Item 16 should be the dial voltage.
This has been on my mind all week and I was finally able to get back to it and check it out. Let's see if I can answer all of this for you. There are a few scenarios, so Ill try to be specific for each one. Cable not sticky, when I loosen the clamp on the stepper shaft I am easily able to move the cable in and out. Seems pretty smooth to me. I can get into the mode where it tells me the rpms and the items below, I am not sure if this is the service mode or not. I just received my chinese Dr.Ex and cable, have not even started to try to get that working yet. The machine has been used a few hours and when I got to the machine the dial had to be turned to L to keep RPMs at 900, anything below L and the machine starts shuddering and just about dies. Machine Dial at L RPM display at 900 Center voltage on stepper connector 2.8 0 0 1 0 2 0.8 3 0.6 4 0 5 0 6 1380 (goes to 800 when dial is at L, 1750 when dial is at H) 7 2.8 8 2.1 (goes to 4.5 when dial is at H) 9 0 A 0.1 B 0 C 0 D 0 E 0 F 0 L1 E L2 E I turned the machine off and ran a stepper mode learning procedure. Upon restarting the machine the RPMs pretty much stayed at 900 from L to H. I loosened the clamp and adjusted the cable out to get the machine to show 2100rpms at H. Now when I go to L I get 1600rpms and all the way to idle I am still at 1900 The voltage on the stepper motor connector center pin is still 2.8V with dial at H. Item 6 - after all this I watch item 6 as a I moved the dial from idle to H and the value goes from 800-1750. I can take it out of Performance mode and go to Economy and the 1750 drops to 1700. Just going off of gut feeling, this feels like the stepper motor is weak internally and slowly loses its position the more you start and stop the machine. When the machine is running at 2150rpm, it will run like that for hours and hours and stay steady. You can lower the rpms and raise them back up and everything is fine. The more you turn the machine off and back it seems the more the idle and max H rpms drop. Thanks a ton for all the help!
This one says no active codes. This is the target rpm. That is the rpm at which the PVC will destroke the hydraulic pumps if the rpm drops below that. It is to reduce the hydraulic load on the engine if it exceeds the output torque of the engine. Too high, has to be 2.5-2.6 at low idle. I sent you a PM.
Thanks for the procedures. Definitely helping in putting together the pieces. I am getting mixed results during troubleshooting. The following is what I went through yesterday.+ 1. Followed and performed the EC learn procedure, including removing the throttle cable clamp from the EC shaft. Then removing the 4 wire connector during the 4 second pause. 2. Read 2.52 at lowest dial position and then adjusted rpms to 1000rpm using the throttle cable clamp With dial turned to H, I was only at 1265rpm and the center wire was measuring only 2.66v 3. Turned machine off 4. Restart at lowest, now 939rpm and 2.53v, dial turned to H was 1200rpm 2.64v 5. I tried this a few more times and could not get a good result. At one point I turned the machine on with 1000rpms at the lowest dial position and as I rev'd up the engine it reached max rpm 2200 before the dial even made it to the "L". 6. At some point I was only able to read 1.8V at the center wire. I didn't seem to get good results with this method so I switched back to the other E-learn method discussed in these forums and in manual. 7. I turned off the machine and performed learning with E switch in the fuse box. 8. Turned machine on, lowest dial position was reading 930rpm, 2.54v, Highest dial position was 1915 at 2.94v, better, not quite 2150rpm, but workable. 9. Turned off and perform e switch learning with E switch in fuse box again, one of the documents said that the learning may need to be repeated a few times, so figured I would try a few times. 10. Turned machine on at lowest dial position and read 950rpm, 2.54v, then at highest position 1865rpm and 2.93v For the most part I am reading the correct voltages on the center wire of the three wire connector. Per one of the procedures sent I confirmed that it appears the 4 wire connector has the correct voltages. Again confirmed the throttle cable was easy to move in and out. I did not check the rpms at the stops as far as I can tell. The rpms still seem to be low and from past experience the next few times I use the machine it will continue to drop. I will report back the voltages when that happens. Is the throttle dial simply a reostat that is sending the 2.5V to that center wire? Your help is much appreciated!
This needs to be done. The throttle dial sends voltage to the PVC. Then the PVC commands the EC based on that voltage. The center wire for the EC Position sensor is feedback to the PVC for confirmation of position. When you do have 1800-1900 hi idle speeds is the dial voltage at 4.5 (#8 on the screen)? It might pay to get DrZx Palm Pilot for troubleshooting. I hope you did not disconnect the 4 pin connector at the EC while the key was on. That could smoke a PVC.
Finally back at the machine. When I said that I did not check the stops, I did not directly. Thinking back the controller troubles I have been going through have basically done this for me. That one time the machine maxed itself out when the dial was merely at L, I was seeing around 2280rpm or right around there. definitely above 2200 and below 2300. It did not get higher, you could hear the engine being rev'd super high. As far as min goes, when the machine is acting up the dial will drop the rpms low enough to kill the engine, it starts acting up big time as it drops below 700rpms. Thanks for the info on how the PVC and EC and dial work together. Based on my previous data, when the max rpm at "H" was only 1750, the indicated voltage on #8 was 4.5V. This basically means the dial is sending the right commands to the EC, which I believe I have verified on the 4pin connector, but the EC is not getting to the correct position, based on the low voltage in the middle of the 3pin. Or it is somehow losing it's "home" position when the key goes off. I did not disconnect the 4pin with the key on, the instructions were to turn the key off, listen to the first adjustment and disconnect during the pause before the second adjustment. I was thinking of disassembling the EC and checking it out, maybe cleaning it.
My throttle has failed completely. When I turn on ignition, I hear the stepper motor go one way to the end ,rattle loud for 10+ seconds ,then go the other way and do the same and stay there in the stopper pulled position. I opened the top ECU and it bad corrossion in a few areas. Has any one purshased an after market chinese ECU? Do they need programming?
I was having issues with having to basically recalibrate the stepper motor every time I started the machine. I continued doing this until one day it started making pretty gross racket when I tried to calibrate, the machine would then turn on full throttle and would not adjust. I found my issue and fixed it and have been waiting to get back on here and give the machine time to ensure it is really fixed. I too started hearing more of a loud clattering and decided to just take apart the stepper motor assembly for inspection. I found oil/grease with lots of dirt and junk on the inside and a broken rubber gear. I imagine the junk got in there from a failed seal, then wedged in the gear and wore it out over time. The stepper motor itself was very clean and would likely work perfect. What I have found is that the rubber gear is on the position sensor shaft and during the calibration procedure it is made to strip out a few times once maxed out, thus being rubber. It took some looking, but found the replacement rubber gear, but it was $40 and took weeks to get in, while the stepper motor was $140 and took a few days. I didnt know for a fact that the stepper motor was going to fix it all, so I went with the cheapest option. I installed, calibrated, adjusted the throttle to spec and so far it has worked flawlessly. I appreciate all of the effort in helping me understand more about this system!
Fitted ecu, reset motor center position and ran throttle learning. Same ****. Ripped stepper motor and that rubber gear has 1 tooth missing. I have an old motor round here somewhere but it is hiding on me at the minute. Hopefully that will cure mine aswell. Not sorry (yet) for changing ecu as i think the old one may have been a fire hazard. Is your machine still working Wits_End? Where did u get the gear?
You can get the gear on ebay from China, search for Hitachi Rubber Gear, I see prices from $45-75. I purchased the entire stepper motor off ebay for $140. The machine is working great.